A tiltrotor aircraft combines VTOL capability (VTOL: Vertical Takeoff and Landing) with efficient long-range cruise performance. Along with advantages of the tiltrotor configuration, there are concerns such as tiltrotor aeroelastic instabilities, rotor-wing aerodynamic interference, gust response characteristics and control characteristics in transition flight. In the present paper comprehensive rigid and aeroelastic analyses that can predict the performance, vibratory loads and aeroelastic stability of composite-coupled advanced geometry tiltrotors that include gimballed hub, elastic wing and elastic fuselage motion are presented. Helicopter, conversion and airplane modes of operation are modeled. The following conclusions are drawn from comparing the rigid blade predictions with other predictions and test data: the rigid analysis captures the occurrence of whirl flutter instability in the wing modes, as well as the elastic blade analysis; predicted whirl flutter speed variation with pitch-flap coupling correlates well with test data but does not predict the behavior of the blade modes accurately. A limited correlation between the elastic blade analysis, flight test and wind tunnel test data of an XV-15 rotor for performance, trim, loads and stability is presented. Based on this limited correlation the following conclusions are made: the predictions of fuselage pitch attitude, rotor collective pitch, gimbal response and rotor torque variation with airspeed compare well with the test data; predicted stability frequencies for the wing beam, chord and torsion modes compare well with flight test data and predictions of wing beam mode damping compare well with full-scale tunnel test data und with results from other analyses.
Validation of a comprehensive aeroelastic analysis for tiltrotor aircraft
Die Validierung einer umfangreichen aeroelastischen Analyse für ein Schwenkrotor-Flugzeug
Journal of the American Helicopter Society ; 43 , 4 ; 333-341
1998
9 Seiten, 13 Bilder, 3 Tabellen, 18 Quellen
Aufsatz (Zeitschrift)
Englisch
Senkrechtstarter , Rotor (Drehflügel) , Schwingungsanregung , dynamische Beanspruchung , Nabe , analytische Untersuchung , Zuverlässigkeitsvoraussage , elastische Eigenschaft , Tragflügel , Flugzeugrumpf , Flugverhalten , Windkanal , Vergleichsmessung , Instabilität , Aerodynamik , Bewegungsgleichung
Validation of a Comprehensive Aeroelastic Analysis for Tiltrotor Aircraft
Online Contents | 1998
|Validation of a Comprehensive Aeroelastic Analysis for Tiltrotor Aircraft
British Library Conference Proceedings | 1996
|Formulation of a comprehensive aeroelastic analysis for tiltrotor aircraft
Tema Archiv | 1996
|Formulation of a Comprehensive Aeroelastic Analysis for Tiltrotor Aircraft
British Library Conference Proceedings | 1996
|